Elevator safety device



P. GROSS ELEVATOR SAFETY DEVICE Dec. 16,1941.

Fileid Jan. 3l, 1941 INVENTOR ATTOR N EYS WITN E55 Patented Dec. 16,1941 ELEVATOR SAFETY DEVICE Paul Gross, Wallace, Idaho, assigner ofone-fourth to Mendel J oy, Mullan, Idaho Application January 31, 1941,Serial No. 376,917

(Cl. IS7-87) 4 Claims.

This invention relates to safety devices for elevators, and its generalobject is to provide a dev1ce that is primarily designed for the usualmine hoist, but it can be used on any passenger and freight elevator ofthe cable hoisting cage and parallel side guide type, as my deviceincludes toothed means that are normally spaced from the guides, but inthe event the cable or any of the hoisting apparatus should break toallow free falling of the cage, the device is automatically renderedactive for moving the toothed means in gripping and penetratingengagement with the guides to `arrest the descension of the cagesubstantially simultaneously with the breakage, thus eliminating injuryor damage, as will be apparent.

A further object is rto provide a safety device that can be easilyinstalled on elevators now in general use, and will in no way interferewith the normal operation thereof.

Another object is to provide a safety device that requires minimumattention, as the parts thereof are normally inactive and are renderedactive only in the event of breakage, as above set forth.

A still further object is to provide a safety device that is simple inconstruction, inexpensive to manufacture and extremely efficient inoperation, use and service.

This invention also consists in certain other features of constructionand in the combination and arrangement of the several parts, to behereinafter fully described, illustrated in the accompanying drawing andspecifically pointed out in the appended claims.

In describing the invention in detail, reference will be had to theaccompanying drawing wherein like characters denote like orcorresponding parts throughout the several views, and in which:

Figure 1 is a sectional view taken approximately on line I-I of Figure2, looking in the direction of the arrows and illustrates the parts innormal position.

Figure 2 is a sectional view taken approximately on line 2-2 of Figure1, looking in the direction of the arrows.

Figure 3 is a fragmentary sectional view similar to Figure 2, butillustrates the parts in operatve position.

Referring to the drawing in detail, the letter A broadly indicates theframe for the cage shaft and while I have illustrated only the centerguide members B for the cage, it will be obvious that the frame is ofthe usual construction. C indicates the lifting cable and D the upperwall or portion of the cage.

The device which forms the subject matter of the present inventionincludes a rectangular sectional casing made up of an outer section thatis provided with an upper horizontal wall I welded or otherwise fixed tothe Wall or portion D of the cage, and side walls 2 having inwardly eX-tending end and bottom flanges 3 and 4 respectively. The upper wall I islikewise provided with depending flanges 5 throughout the lengththereof, as best shown in Figure 2. The inner section is substantiallyU-shaped to provide a bottom wall 6 and side walls 1 and is of lessheight than that of the outer section, but otherwise fits therein forfree vertical movement between the upper wall I and the bottom flanges4.

Bolted or otherwise secured to the bottom wall 6 of the inner sectionand extending through a slot in the upper wall I is a coupling bar 8having the cable C connected to the upper end thereof, so that thecage'will be connected to the cable through the medium of my device.Formed on opposed sides of the coupling bar' are pairs of stop lugs 9and I0, the lugs 9 being disposed above the casing for engagement withthe upper surface of the upper wall I, while the lugs I0 are arranged onthe bar 8 for disposal within the casing for engagement with the undersurface of the upper wall I, as will be apparent upon inspection ofFigure 2, which clearly illustrates that the lower lugs I0 are normallyengaged with the wall I.

Disposed within the casing and having threaded shanks II threadedthrough the upper wall I are disk abutment members I2 for the upper endsof compression springs I3 that have their lower ends bearing against thebottom wall 6 for urging the inner section downwardly to the position ofFigure 3, and the spring elements are arranged along the longitudinalcenter of the casing, as shown in Figure 2. In view of the fact that theabutment members I2 are threadedly associated with the wall I, it willbe obvious that the tension of the springs I3 can be adjusted, byrotating the disk members.

Secured tothe end walls 2 and extending inwardly and downwardlytherefrom in converging relation with respect to each other, are pairsof bracket arms I4 terminating at their lower ends in bearings I5 havingmounted for rotation therein a pair of parallel rock shafts I6. Each ofthe shafts I6 have toothed dogs I'I keyed or otherwise fixed to thenouter ends thereof for normal disposal in parallelism with and uponopposite sides of the guide members B, as best shown in Figure 2. Thedogs increase in width from their connection with the shafts to providerelatively long arcuate outer faces having teeth i8 formed thereon forthe major portion of their length, with the teeth extending from one endof the faces, while the opposite end portions of the faces are free fromteeth, as clearly shown in Figure 3. That feature not only tends toincrease the gripping and penetrating action of the dogs, but preventssplitting or breakage of the guide members B.

Welded or otherwise secured to and depending from the bottom wall 6 ofthe inner section are semidisk shaped ears I9 arranged in pairs and eachear has connected thereto through the medium of links 20, a cam member2l, that is held in constant engagement with its ear', but for movementthereon, from the position of Figure 2, to that of Figure 3, as the pins22 that connect the links 20 to the cam members are mounted in arcuateslots 23 of the cam members to bring about said movement. The majorportions of the ycam members are oval shaped but they are formed toprovide substantially disk like portions 24 on one of the ends thereof,and the cam members are keyed or otherwise secured to the shaft I6 withthe latter extending through the disk like portions.

From the above description and disclosure in the drawing, it is believedthat the operation of my device will be obvious, but it might bementioned that in the event the cable C or any part of the hoistingapparatus. should break, to allow free falling of the cage, the weightof the cage will be released from the bar 8 and consequently the innersection will be lowered in the outer section by the action of thesprings I3. That movement of the inner section will cause the ears I9 toexert a bearing action against the cam members and thereby move thelatter from the position of Figure 2 to that of Figure 3, so as to rockthe shafts I', for the latter to move the dogs in biting engagement withthe'` opposite sides of the guide members B, as shown in Figure 3. B-ythat action, it will be seen that the' descension of the cage isarrested and such is brought about substantially simultaneously withythe breakage, thus my device not only arrests the cage but does so in a.man-ner to prevent any possibility of injury or damage, assufcient timedoes not elapse between the breakage and the stop for the cage to gatherany material' momentum.

It is thought fromV the foregoing description that the advantages andnovel* features of the invention will be readily apparent.

It is to be understood that. changes may be made in the construction.and in the combination and arrangement of the several parts, providedthat such changes fall within the scope of the appendedA claims.

What I claim is:

1. A safety device for an elevator, the latter including a cage, ahoisting cable and guides for the cage, and said device comprising acasing including an outer section having an upper wall fixed to thecage, sid'ewalls depending from the upper wall, inwardly extendingmarginalflanges on said walls, an inner section including a bottom walland side walls rising from the bottom wall, said inner section beingmounted for vertical. movement in the outer' section and held therein bythe walls' and flanges thereof, a coupling' bar fixed to the bottomwallf and extending through the upper wall, stop means on the couplingbar to limit the movement of the inner section, coiled springs betweenthe upper and bottom walls for urging the inner section downwardly,abutting means for the springs and adjustably mounted in the upper wallfor adjusting the springs, said bar having the cable connected theretofor normally holding the springs contracted, toothed dogs mounted fornormal disposal in spaced relation to the guides, and means carried bythe inner section for moving the dogs into biting engagement with theguides.

2. A safety device for an elevator, the latter 'including a cage, ahoisting cable and guides for the cage, and said device comprising meansincluding inner and outer sections, the outer section being fixed to thecage and the inner section mounted for vertical movement in the outersection, a coupling b-ar fixed to the inner section and extendingvertically through the outer section, springs between the sections forurging the inner section downwardly, said bar having the cable connectedthereto for normally holding the springs contracted, brackets armssecured to the outer section and depending therefrom in convergingrelation with respect to each other, shafts mounted for rocking movementin the lower ends of the bracket arms, toothed means fixed; to theshafts and normally held spaced from the guides, rounded ears xed to theinner section, cam means connected to and engaged with the rounded ears,and said cam means being xed to the shafts for rocking the latter tomove the toothed means into biting engagement with the guides.

3. A safety device for a cage, a hoisting cable and guides for` thecage, and. said device comprising means including inner and outersections, the outer section being xed to the cage and the inner sectionmounted for vertical movement in the outer section,ra-coupling bar fixedto the inner section and extending vertically through the outer section,springs between the sections for urging the inner section downwardly,said bar having the cab-le connected thereto for normally holding thesprings contracted, bracket means fixed to and depending from the outersection in converging relation, shafts mounted in the lower ends of thebracket means for rocking movement, toothed dogs fixed at one of theirends to the shafts andthe opposite ends being relatively wide and shapedto provide arcuate faces with the teeth formed on a portion of saidfaces, said dogs being arranged for normal disposal in spaced relationto the guides, and means carried by the inner section and connected tothe shafts for rocking the latter to move the dogs into bitingengagement with the guides.

4L, A safety device for an elevator, the latter including a cage, ahoisting cable and guides for the cage, and said device comprising meansinciuding inner and outer sections, the outer section being Xed to thecage and the inner section mounted for vertical movement in the outersection, a coupling bar fixed to the inner section.

and extending vertically through the outer section, springs between thesections for urging the inner section downwardly, said `bar having thecable connected thereto for normally holding the springs contracted,bracket arms secured to and depending from the outer section inconverging relation with respect to each other, shafts mounted forrocking movement in the lower ends of! theA bracket arms, toothed dogs'fixed-to the ends ofthe shaft and normally held:

for the cam members being mounted in the slots thereof, and disk likeportions formed on the oval shaped portions and keyed to the shafts forrocking the latter to move the dogs into biting 5 engagement with theguides.

PAUL GROSS.

